Systems and methods for assessing and modifying an individual&#39;s physiological condition

ABSTRACT

Systems and methods for assessing an individual&#39;s physiological condition are provided. Cycle and shape parameters are derived from a recorded time trace containing heart rate data collected while an individual performs a cyclic exercise routine. Individually tailored exercise regimens that are based on these parameters are generated and modified as desired.

This application claims priority from U.S. patent application Ser. No.09/609,087, filed Jun. 30, 2000, which is now abandoned.

BACKGROUND OF THE INVENTION

This invention relates generally to systems and methods for assessingand modifying an individual's physiological condition. Moreparticularly, this invention relates to systems and methods forassessing and modifying an individual's physiological condition byanalyzing heart rate data collected while the individual is exercisingaccording to an exercise regimen.

The human physiological condition is the result of complex interactionsbetween various underlying phenomena that are internal as well asexternal to the human body. For example, cardiac activity is anaccumulation of complex interactions between various internal phenomenasuch as muscular, neurological, vascular, pulmonary, endocrinal,chemical, and cellular phenomena. Cardiac activity also responds toexternal behavioral activity, such as physical activity that causesenergy expenditure and recovery, and to naturally occurringenvironmental phenomena, such as day-night cycles, lunar cycles, andweather seasons.

A perspective view of human physiology enables one to describephysiological functions in terms of wave phenomena made up of asuperposition of other underlying wave phenomena. For example, cardiacactivity manifests itself through repetitive pulsations of the heart asa heart wave. The heart wave is a result of a superposition of manyunderlying waves (i.e., cycles) including behavioral waves (e.g., energyexpenditure and recovery cycles in response to physical activity),environmental waves (e.g., day-night cycles), and internal waves (e.g.,molecular biological, cellular, and chemical cycles).

Heart rate variability (i.e., the variation in an individual's heartrate) is another manifestation of the superimposed effects of variousendogenous and exogenous phenomena on human physiology. Decreased heartrate variability has been associated with abnormal physiologicalconditions and increased mortality. Treatments which increase heart ratevariability in an individual's serve both therapeutic as well asprophylactic purposes. Dardik U.S. Pat. Nos. 5,007,430, 5,800,737,5,163,439, and 5,752,521, which are hereby incorporated by reference intheir entireties, further elaborate on the wave nature of cardiacactivity.

Current methods for analyzing cardiac activity, however, are inadequatebecause they do not analyze the cyclical properties of heart waves witha view to unraveling details of their superimposed wave structure. Inthe absence of quantitative information on the cyclical properties ofheart waves, it is difficult to provide a complete or accurateassessment of an individual's physiological condition, and individuallytailor exercise regimens. For example, most methods of prescribingexercise regimens are often based on general criteria, such as age,rather than an individual's actual physiological condition.

It would therefore be desirable to have systems and methods that morecompletely and quantitatively characterize heart waves.

It would further be desirable to characterize heart waves in a mannerthat provides an accurate quantitative metric of an individual'sphysiological condition.

It would also be desirable to be able to generate individually tailoredexercise regimens for modifying an individual's physiological condition,based on a quantitative metric.

SUMMARY AND OBJECTS OF THE INVENTION

It is an object of the present invention to provide systems and methodsfor-a detailed characterization of heart waves that enables a relativelycomplete assessment of an individual's physiological condition.

It is a further object of the present invention to provide quantitativemetrics of an individual's physiological condition, based on detailedcharacterization of cyclic properties of heart waves.

It is also an object of the present invention to provide systems andmethods for generating individually tailored exercise regimens that areindependent of general criteria, such as age, but are based on moreexperimentally determined metrics.

It is a still further object of the present invention to provide systemsand methods for generating individually tailored exercise regimens basedon these metrics, with a goal of increasing heart rate variability.

These and other objects of the invention are accomplished in accordancewith the principles of the present invention by providing systems andmethods for assessing an individual's physiological condition byextracting cycle parameters from a recorded time trace of heart ratedata collected while an individual is exercising according to anexercise regimen. While exercising, the individual's heart wave includesenergy expenditure and recovery cycles in response to cycles of physicalactivity. The cycle parameters containing relevant information caninclude discrete parameters and shape specific parameters. Discreteparameters include, for example, maximum, minimum, and resting heartrates, as well as upward, downward, and baseline slopes. The shapespecific parameters (discussed below) can be used to characterize theshapes of portions of the time trace that are believed to containphysiologically important information. Based on these parameters, anindividual's physiological condition can be quantified (e.g., in a heartwave index or a capacity index), which can incorporate some or all ofthe relevant physiological information contained in a time trace.

The quantitative figure of merit can be used to gauge the progress of anindividual under an exercise regimen and to design individually tailoredexercise regimens for modifying the individual's physiologicalcondition. When used, exercise regimens modify the individual'scondition by shaping the heart wave with a goal of increasing theindividual's heart rate variability. Individualized heart wave shapingcan be achieved in accordance with this invention by application of theprinciples for therapeutic treatment and bio-rhythmic feed back taughtby Dardik, U.S. Pat. Nos. 5,800,737, 5,752,521, 5,163,439, and5,007,430.

According to one embodiment of the present invention, an exerciseregimen having at least one exercise session that contains one or moreexercise cycles is used for assessing an individual's physiologicalcondition. The individual's heart rate is monitored during the exercisesession, and a time trace of the heart rate is recorded in an electronicfile. Then, the time trace is analyzed to determine one or more cycleparameters, such as a peak heart rate, a minimum heart rate, a restingheart rate, and a base line slope. These parameters can then be used todetermine a heart wave index indicative of the individual'sphysiological condition.

Additional parameters, such as parabolic coefficients, whichcharacterize the shape of one or more portions of the time trace, canalso be obtained. These parameters can also be incorporated into theheart wave index or another figure of merit.

According to another aspect of this invention, a quantitativedetermination of an individual's physiological condition or capabilitycan be used to prescribe an exercise regimen. In one embodiment of thisinvention, an individual is subject to an exercise test to determine aninitial physiological capability. During the test the individual's heartrate is monitored and preferably stored in the form of an electronicfile. The test typically includes at least one, and preferably severalexercise cycles, including a maximum effort cycle in which theindividual attempts to exercise to the individual's maximum capability.Cycle parameters are then obtained by analyzing the heart rate data. Thecycle parameters (such as those that characterize the maximum effortcycle) can be incorporated into a figure of merit. Then, anindividualized exercise regimen can be generated using an algorithm thatrelates the figure of merit, or the cycle parameters directly, toexercise regimens.

In accordance with the principles of the present invention, a system forassessing an individual's physiological condition or capability includesat least an electronic monitor, a recorder, and an analyzer. The monitormonitors the individual's heart rate. The recorder records a time traceof the individual heart rate in an electronic file. The analyzeranalyzes the electronic file, using one or more routines (i.e.,procedures, programs, or algorithms) to, for example, determine at leastone cycle parameter, such as a peak heart rate, a maximum heart rate, aminimum heart rate, an upward slope, a downward slope, and a base lineslope. The analyzer can derive shape parameters by fitting one or moreparabolas or other mathematical models to portions of the time trace,and can determine a figure of merit based on the determined cycleparameters.

According to another aspect of this invention, electronic networks, suchas the Internet, can be used to receive data and provide information tothe individual remotely.

BRIEF DESCRIPTION OF THE DRAWINGS AND THE APPENDIX

The above and other objects and advantages of the present invention willbe apparent upon consideration of the following detailed description,taken in conjunction with the accompanying drawings, in which likereference characters refer to like parts throughout, and in which:

FIG. 1 is a schematic block diagram of an illustrative systemconstructed in accordance with the present invention;

FIG. 2 is an illustrative exercise regimen that can be generated andused in accordance with the present invention;

FIG. 3 is an illustrative time trace of heart rate data collected overan exercise session, in accordance with the present invention;

FIG. 3 a is an illustrative time trace of heart rate data collected overan exercise cycle, in accordance with the present invention;

FIG. 4 is an illustrative top portion of a cycle in a time traceincluding an illustrative theoretical parabola that has been fit theretoin accordance with the present invention;

FIG. 5 shows two illustrative top portions of a time trace, eachcorresponding to an abnormal physiological condition, including twoillustrative theoretical parabolas that have been fit thereto, inaccordance with present invention;

FIGS. 6 a, 6 b and 6 c show three illustrative time traces havingcumulative rest portions with varying degrees of parabolicitycorresponding to good, moderate and poor physiological conditions,respectively;

FIG. 7 is an illustrative look-up table that can be used in accordancewith this invention; and

FIG. 8 is an illustrative exercise regimen that has been generated inaccordance with the present invention;

FIG. 9 is a flow chart of a process used to extract cycle parametersfrom a time trace, in accordance with the present invention;

FIG. 10 is a flow chart of a process used to extract shape parametersfrom top portions of a time trace, in accordance with the presentinvention;

FIG. 11 is a flow chart of a process used to extract shape parametersfrom rest portions of a time trace, in accordance with the presentinvention; and

Appendix A contains actual exercise regimens appropriate for individualswith nominal capacity indices ranging from 120 to 180 units, inaccordance with this invention.

DETAILED DESCRIPTION OF THE INVENTION

In order that the invention herein described can be fully understood,the following detailed description is set forth.

FIG. 1 shows illustrative systems for assessing an individual'sphysiological condition during performance of an exercise regimen.Individual 10 is shown exercising on exerciser 20. Exerciser 20, forexample, can be a treadmill machine, a trampoline, a stationary bicycle,or any other suitable exercising apparatus. Exerciser 20, however, isoptional because exercise can be done without the aid of an exerciseapparatus (e.g., running, jogging, jumping, walking, moving arms andshoulders, or swinging legs). Electronic monitor 30 monitors the heartrate of individual 10.

Monitor 30 can be any commercially available unit that measures theheart rate and transmits heart rate data to recorder 40 through link 50.Link 50 can be, for example, a magnetic coupling, a wirelesstransmission system, or any other electronic or electromagnetic network.Monitor 30 can be connected through link 50 to user interface 60.Interface 60 can provide to users visual, auditory, or tactileinformation regarding the heart rate or any other type of data. Recorder40 can be, for example, a printer, a chart recorder, or other device (orcombination of devices) that can record the time trace in an electronicfile 70.

Monitor 30, recorder 40, link 50, and interface 60 can be obtainedcommercially as an integrated heart monitoring and recording unit (suchas Model Polar M52 or Model Polar NV sold under the trademark POLAR™, byPolar Electro Inc., of Woodbury, N.Y.). Link 80 connects recorder 40 toanalyzer 90, and can be local or remote to exerciser 20. According toone embodiment, and as shown in FIG. 1, link 80 can include watchreading interface 81 (such as “Polar Advantage Interface System” Model900622K sold under the under the trademark POLAR™, also by Polar ElectroInc.), personal computer 82, and Internet link 83. It will beappreciated, however, that link 80 can be any electronic network thatcouples recorder 40 to analyzer 90 for data communication.

Analyzer 90 can include one or more electronic computing devices,preferably programmable computing devices (such as Model HP-VEE sold byHewlett Packard Company, of Palo Alto, Calif.). It will be appreciatedthat analysis could, in some cases, involve manual computation orreview. Analyzer 90 analyzes electronic file 70, which contains at leastone time trace of the heart rate, to determine at least one exercisecycle parameter (e.g., a maximum heart rate). Based on that parameter,analyzer 90 can calculate a heart wave index indicative of theindividual's physiological condition.

FIG. 2 shows illustrative exercise regimen 200, which includes exercisesession 201. FIG. 3 shows corresponding illustrative time trace 300 ofan individual's heart rate, when exercising according to session 201.Exercise session 201 includes five successive exercise cycles 210–214 ofincreasing difficulty with each of cycles 210–214 associated withgenerally increasing target heart rates 215–219. It will be appreciatedthat an exercise session according to this invention could include moreor less than five cycles and that the target heart rates need notincrease monotonically.

In each of exercise cycles 210–214, the individual is expected tocommence physical activity and continue the activity over first timeperiod 222 in an attempt to raise the heart rate to one of respectivetarget heart rates 215–219. Period 222 can be fixed or variable.Preferably, period 222 is variable but has an upper time limit. Whenperiod 222 is variable and has an upper time limit (e.g., variable cycle214), the individual exercises only until either the target heart rateis reached or the upper time limit is reached. Preferably, the uppertime limit is about one minute. However, when period 222 is fixed, theindividual exercises for a fixed amount of time even if the individual'sheart rate goes over or stays under the target heart rate. Period 222when fixed is preferably between about 30 seconds and about 90 seconds,and more preferably about one minute (e.g., cycles 210–213).

One type of variable cycle is a spike cycle. In spike cycle 214(represented as “S”), an individual exercises as vigorously as possibleto reach target heart rate 219 in as short a time as possible. Thus, theactual time period depends on the condition of the individual.

In each cycle 210–214, after initial period 222, the individual relaxesduring time period 223 by gradually diminishing, or preferably, byabruptly ceasing physical activity. Period 223 can also be fixed orvariable. Preferably, period 223 is variable and ends when the heartrate substantially stabilizes (i.e., levels off). A heart rate can beconsidered “stabilized” when the heart rate changes less than a certainamount over a pre-determined period of time. For example, a heart ratecan be considered to be stabilized when the heart rate changes less thanabout 3 beats/min. over an interval, such as a one minute interval.

Exercise session 201 can include intervening rest periods 224 betweensuccessive exercise cycles 210–214. Additional intervening rest period224 can also be inserted before post-exercise recovery period 225. Restperiods 221, 224, and 225 can have fixed durations or can be determinedby the individual's performance by the amount of time required for theheart rate to substantially stabilize.

A time trace can contain heart rate data collected over any time periodranging, for example, from a few seconds to several days. Thus a timetrace can include data collected over a single or multiple exercisecycles, sessions, or regimens. FIG. 3 shows illustrative time trace 300of an individual's heart rate during exercise session 201. Trace 300includes pre-exercise portion 310, which represents the heart rateduring time period 221. During period 221, the individual can staystill, acclimatize to exerciser 20 and surroundings, and allow the heartrate to stabilize over several minutes before commencing an exercisecycle. Portion 310 is believed to contain information on theindividual's resting heart rate and can serve as a reference or baseline heart rate from which to assess changes in the individual'sphysiological condition, for example, due to exercise.

Each of portions 320 represents a rising heart rate during each of timeperiods 222 (FIG. 2). It is believed that each of portions 320 containsphysiological information on the individual's ability to sustainincreasing stress.

Each of portions 330 represents a portion of an exercise cycle in whichthe heart rate of the individual falls. The heart rate often exhibits anatural overshoot phenomena at the end of portion 330, typically fallingbelow an initial base line heart rate (prior to cycles 210–214). Afterovershooting, the heart rate normally recovers to a new base line heartrate. Portion 330 is believed to contain physiological information onthe individual's short term ability to recover from stress.

Each of top portions 325 represents the heart rate as it transitionsbetween periods 222 and 224, which roughly correspond to time traceportions 320 and 330. In each of cycles 210–214, the individual attainsa peak (i.e., maximum) heart rate during top portion 325. Peak heartrates have been found to be a significant measure of an individual'sphysiological condition.

Each of portions 340 represents the heart rate during stabilizingperiods 224 which allow the individual's heart rate to stabilize betweencycles 210–214. Portions 340 are believed to contain physiologicalinformation on shifts in the resting heart rates to new base line levelsin response to exercise cycles 210–214.

Portion 350 represents the heart rate during post-exercise recoveryperiod 225. Portion 350 is believed to contain physiological informationon an individual's ability to recover from the cumulative effects ofexercise cycles 210–214, including any shift in base line heart rates.

An assessment of an individual's physiological condition can bequantified in a figure of merit (e.g., a heart wave index). This figurecan incorporate some or all of the relevant physiological informationcontained in a time trace of the heart rate, including any of the cycleparameters discussed herein. A heart wave index, for example, is asingle metric that can be used to summarize an assessment of thephysiological condition. The heart wave index can also be regularlydetermined and used to gauge the progress of an individual under anexercise regimen. Use of one or more quantitative figures of meritenables an accurate determination of causes and effects of changes thatoccur in an individual's physiological condition based on an exerciseroutine. As explained more fully below, exercise regimens for anindividual can be designed to cause specific changes in an individual'sheart wave index.

Information contained in a time trace can be characterized by cycleparameters (such as peak heart rates, minimum heart rates, upward slopesand downward slopes), that are achieved during one or more exercisecycles in an exercise regimen. Other cycle parameters such as baselineslopes and resting heart rates can be used to characterize pre-exercise,intervening, and post-exercise rest periods.

Information contained in a time trace can be further characterized byshape specific cycle parameters that describe the shapes of portions ofthe time trace. These shape parameters can be incorporated into theheart wave index. For example, cycle parameters that describe theparabolicity of a top portion or a rest portion can be used to determinea heart wave index. Moreover, multiple shape parameters can be used incombination. For example, parabolic coefficients can be used incombination of baseline slopes.

A time trace can be analyzed to determine a maximum heart rate achievedby the individual in the course of an exercise session. According to oneembodiment of the present invention this maximum rate serves as theheart wave index that is used to determine the target heart rates in anindividually tailored exercise regimen.

A time trace can be further analyzed to determine other cycleparameters, such as an upward slope S_(up), a downward slope S_(down) apeak heart rate R_(peak), and a minimum heart rate R_(min). FIG. 3 ashows an illustrative cycle 214 of time trace 300. Starting heart rateR₀ is determined by finding the heart rate at time t₀, at or about thestart of period 222. Peak heart rate R_(peak) and corresponding time t₅are determined by finding the highest heart rate datum within topportion 325. Time t₅ is often located at or about the end of period 222by which time the target heart rate has been reached. Minimum heart rateR_(min) and corresponding time t₆, are determined by finding the lowestheart rate datum in portion 330. Time t₆ is often located at or aboutthe end of period 223 by which time the heart rate has stabilized.

The upward slope can be calculated as a derivative, for example, usingthe change in the heart rate from R₀ to R_(peak) over all of portion 320(corresponding to time period 222), substantially according to:S _(up)=(Rpeak−R ₀)/(T ₅ −t ₀)

The downward slope can also be calculated as a derivative, for example,using the change in the heart rate from R_(peak) to R_(min),substantially according to:S _(down)=(Rpeak−R _(min))/(t ₆ −t ₅)

It will be appreciated that other formulations of the upward anddownward slope can be used in accordance with the present invention. Forexample, an upward slope can be calculated by first identifying asegment of portion 320 which is substantially linear. Such asubstantially linear portion is shown in FIG. 3 a as the segment betweenheart rates R₁ and R₂, corresponding to times t₁ and t₂, respectively.Upward slope S_(up) can be calculated according to:S _(up)=(R ₂ −R ₁)/(t ₂ −t ₁)

Similarly, downward slope S_(down) can be calculated by identifying asegment of portion 330 which is substantially linear, such as thesegment between heart rates R₄ and R₅ corresponding to times t₃ and t₄,respectively. Downward slope S_(down) can be calculated according to:S _(down)=(R ₄ −R ₅)/(t ₄ −t ₃)

A heart wave index can be determined using one or more of these cycleparameters. For example, heart wave index HWI can be defined as aweighted sum of at least two of upward slope S_(up), downward slopeR_(down), peak heart rate R_(peak), and minimum heart rate R_(min), forexample, according to:HWI=a R _(peak) +b S _(up) +c S _(down) +d R _(min)where a, b, c and d are weight factors that can be positive, zero, ornegative numbers.

For example, a heart wave index can be a straight linear sum of upwardslope S_(up), downward slope S_(down) and peak heart rate R_(peak). Inthis case, weight factors a, b, and c set are equal to 1, and factor dis equal to zero:HWI=R _(peak) +S _(up) +S _(down)

It will be appreciated that any convenient formulation could be used,depending on the nature or properties of the particular quantities beingmeasured.

A heart wave index could also incorporate one or more other cycleparameters that characterize pre-exercise, intervening and post-exerciserest portions determined from the time trace. For example, resting heartrate R_(rest) can be used to characterize any of rest portions 310, 340,and 350. Resting heart rate R_(rest) can be determined, for example, byaveraging the heart rate after it has substantially stabilized. Further,for example, a base line slope S_(base) can be used to characterize anyone or any combination of rest portions. (A combination of rest portionscan, for example, consist of all of portions 310, 340, and 350). Baseline slope S_(base) can be calculated by determining the change in theheart rate during one or more rest portions, in a manner analogous tothe determination of upward and downward slopes described above.

Thus, the heart wave index can be any function of cycle parameters:HWI=function (cycle parameters).A heart wave index can be equal, for example, to the difference in theresting heart rates determined from portions 310 and 350.

FIG. 9 shows a flow diagram of process 900 of one embodiment used toanalyze a time trace contained in an electronic file. Process 900 beginsat step 910 by selecting or receiving an electronic file for analysis.Next, in step 920, any file headers attached to the electronic file canbe stripped away. In step 930, any header information can be stored in adatabase. Steps 920 and 930 are optional, but can be useful when thefile is received in the form of an e-mail, for example.

In step 950, the time trace is further analyzed by determining variouscycle parameters, such as baseline slope, upward and downward slopes,and/or maxima and minima for each cycle. In addition to determiningcycle parameters, a heart wave index can also be calculated in step 950.In step 960, analysis results are optionally stored in a data base.

Shape parameters can also be derived from the time trace, for example,by fitting one or more top portions 325, or through all of rest portions310, 340 and 350 with a theoretical parabola,y=Ax ² +Bx+C.Regression analysis techniques can be used to fit the parabola to obtaincoefficients A, B, and C. Any suitable statistical test (e.g.,chi-square) can be used to determine the quality of the fit. At leastone goodness of fit parameter (e.g., coefficient of correlation R, orcoefficient of determination R²) that characterizes the quality of thefit can also be calculated.

FIG. 4 illustrates how a parabola can be fit to a top portion, such astop portion 325, to obtain one or more shape parameters. Time traceportion 400 represents a top portion of an exercise cycle. Theoreticalparabola 410 represents a best fit generated, for example, by regressionanalysis. The heart wave index can then be determined using any of thecycle parameters and one or more shape parameters, such as the paraboliccoefficients and one or more goodness of fit parameters. The heart waveindex can itself be equal to a goodness of fit parameter.

FIG. 10 shows a flow diagram of process 1000 of one embodiment used tofit a parabola to top portions contained in an electronic file. In step1001, an electronic file to be analyzed is selected or received. Next,any file headers attached to the electronic file can be stripped. Instep 1020, a maximum heart rate for each relevant cycle is determined,which could involve locating the top portion of each cycle. In step1030, the top portions are fit to theoretical shapes (e.g., parabolas)using, for example, regression analysis. Parabolic coefficients areobtained and at least one goodness of fit parameter is preferablycalculated for each fit. In step 1040, analysis results can optionallybe stored in a data base.

Similarly, FIG. 11 shows a flow diagram of process 1100 of oneembodiment used to fit a parabola to resting portions in a time trace.In step 1101, an electronic file to be analyzed is selected or received.In step 1110, any file headers attached to the electronic file can bestripped away and optionally stored. In step 1120, a minimum heart ratefor each cycle is determined. In step 1130, a recovery baseline ischosen. This can involve determining a portion of the time trace inwhich the heart rate is stabilized after recovering from a minimumdetermined in step 1120. In this manner, rest portions 340 correspondingto each cycle can be identified. In step 1140, regression analysis orany other type of comparable analysis routines are used to fit aparabola to each rest portion. For each fit, parabolic coefficientsand/or at least one goodness of fit parameters can be obtained. In step1150, analysis results can be optionally stored in a data base.

As explained above, the shapes of the top portions and the restingportions are believed to contain information on the physiologicalcondition of the individual. In particular, it has been discovered thatabnormal physiological conditions are often associated withnon-parabolic shapes. FIG. 5 shows a heart rate trace that includes twoillustrative top portions 501 and 502. These portions correspond toabnormal physiological conditions because their shapes deviate stronglyfrom symmetric parabolas 503 and 504, respectively.

FIGS. 6 a, 6 b, and 6 c show actual measured time traces 601, 602, and603, of heart rate data from three different individuals. The timetraces represent heart rate data collected over exercise sessionsconsisting of five exercise cycles (i.e., trace 601 and 602) or sixexercise cycles (I e., trace 603). Analysis of pre-exercise restportions of these traces yields baseline heart rates of 86, 58, and 78beats per minute, respectively.

Analysis also includes identification of peak heart rates and minimumheart rates for each of the last four exercise cycles in each trace. Thepeak heart rates are indicated by square symbols in FIGS. 6 a, 6 b, and6 c. The peak heart rates for the last four cycles in trace 601, indescending order, are 169, 164, 158, and 149 beats per minute.Similarly, for trace 602 the peak heart rates are 169, 165, 168, and 158beats per minute, and for trace 603 the peak heart rates are 105, 102,104, and 95 beats per minute.

Analysis also includes calculating upward and downward slopes for thelast exercise cycle in each trace. For traces 601, 602, and 603, upwardand downward slope pairs have values of (48, 24), (72, 60) and (24, 24),respectively.

In each of FIGS. 6 a, 6 b, and 6 c, the pre-exercise rest portion, theintervening rest portions, and the post-exercise rest portion can becombined to form a cumulative rest portion. Analysis of the leading edgeof the cumulative rest portions yields baseline slopes that arepositive. The magnitude of these slopes is proportional to the rate ofincrease of base line heart rates during the exercise sessions. Thebaseline slopes for traces 601, 602, and 603 are 150.9, 60.3, and 9.4,respectively. These baseline slopes are exemplified with lines 607, 608,and 609, respectively. It has been empirically found that the baselineslope correlates positively with an individual's physiologicalcondition. It is believed that higher (i.e., steeper) baseline slopescorrespond to better physiological conditions. Thus, measurement of abaseline slope can be used to assess an individual's physiologicalcondition and to monitor an individual's progress.

Based on these peak and base line heart rates, baseline, upward, anddownward slopes, heart wave indices for each individual are calculated,for example, according to:HWI=(peak heart rate of last cycle)+baseline slope

By this analysis of traces 601, 602, and 603, heart wave indices of 320,229, and 114 are obtained for the three different individuals,respectively. The relatively low heart wave index of 114 obtained fromthe analysis of trace 603 correlates positively with the poorphysiological condition of the third individual, who was clinicallyfound to suffer from congestive heart disease.

The shape cumulative rest portions of time traces 601, 602, and 603exhibit different degrees of parabolicity, which are believed tocorrespond to good, moderate, and poor physiological conditions,respectively. As an alternate or in addition to baseline slopes, thedegree of parabolicity can be quantified by fitting a parabola to thecumulative rest portion. Fitted parabolas 604–606 exhibiting varyingdegrees of parabolicity are shown in FIGS. 6 a, 6 b, and 6 c,respectively.

Catalogs can be prepared that link measured coefficients and goodness offit parameters, or other theoretical models (e.g., based on baselineslopes) to one or more specific abnormal physiological conditions. Thesecatalogs can be based upon actual clinical data and/or theoretical data.

Abnormal physiological conditions then, can be diagnosed by fitting aparabola through one or more portions of the time trace (e.g., a topportion or a resting portion) to obtain parabolic coefficients and/orgoodness of fit parameters. Abnormal physiological conditions can thenbe identified by determining which of the measured paraboliccoefficients and/or goodness of fit parameters are like those listed inthe catalog. Abnormal physiological conditions which may be amenable todiagnosis in this manner, can include conditions, such as congestiveheart disease, leukemia, anorexia, multiple sclerosis, HIV or otherimmune deficiencies, astrocytoma of the brain, peripheral ischemia andneuropathy, ileitis, chronic hepatitis, and chronic fatigue syndrome.

The present invention also can be used to modify an exercise regimen.First, a representative heart wave index for an individual exercisingunder the regimen is obtained. This heart wave index may represent theresults of analyzing time traces from one or more exercise sessions. Forexample, the representative heart wave index may represent the averageof heart wave indices from the analysis of two consecutive exercisesessions, or the average of highest three of five exercise sessions.

The representative heart wave index is then compared to a target heartwave index associated with the exercise regimen. This comparison is usedto determine a need to modify the exercise regimen, such as when thecomparison indicates that the individual is not benefitting from theexercise regimen. The exercise regimen can be modified to make it moreappropriate to the individual's physiological condition, for example, byraising the target heart rates. In one embodiment of the presentinvention, the target heart rate can be changed in direct proportion tothe difference between the target heart wave index and therepresentative heart wave index. For example, if the representativeheart wave index exceeds the target heart wave index by an amount (e.g.,by 20 units), then the target heart rates in the previous regimen can beuniformly increased by one half of the difference (i.e., by 10 units) inthe modified regimen.

An individual's initial physiological capability can be determined andused to individually tailor and prescribe an exercise regimen.

For example, an individual can be subject to an “exercise test” duringwhich the individual's heart rate is monitored. A time trace isrecorded, for example, on a chart recorder or any other electronicrecording device.

The exercise test can include a plurality of test cycles that may bedesigned to be similar to the exercise cycle described above. The firstfew cycles can be warm-up cycles, followed by a plurality ofintermediate cycles, which are then followed by at least one maximumeffort cycle.

The warm-up cycles can or cannot have defined target heart rates. Theintermediate cycles preferably have target heart rates. Most preferably,each of the intermediate cycles have a target heart rate that is greaterthan that of its immediately preceding cycle. The increase in targetheart rates could vary substantially over an exercise session and insome cases decrease. The amount of the increase, however, is generallyless than about 15 beats per minute. A maximum effort cycle does nothave a fixed target heart rate but requires that the individual exerciseup to the individual's maximum physical capability.

Test cycles can include a stress portion over a fixed time interval ofbetween about 30 seconds and about 90 seconds, followed by a relaxationportion over another time interval. Preferably, the stress portion isover a time interval that is not in excess of about one minute. Therelaxation portion need not be fixed and could be determined by the timeit takes the individual's heart rate to recover and stabilize.

The individual's capability can be assessed in terms of a quantitativefigure of merit based on cycle parameters obtained by analyzing theexercise cycles' time trace. In one embodiment, maximum heart rateR_(max), which is achieved by the individual during each of the testcycles, is determined by analyzing the time trace as described above.Then, a capacity index is assigned a value that is a function of one ormore maximum heart rates. For example, the capacity index can beassigned a value equal to the average of maximum heart rates achievedduring two consecutive maximum effort cycles. Alternatively, a weightedsum could be used.

The time trace can be further analyzed to determine upward slopes anddownward slopes in the manner discussed above. Then, the capacity indexcan be assigned a value based on one or more of test cycle parameters,such as maximum heart rates, upward slopes, and downward slopes. Forexample, the capacity index can be assigned a value equal to a straightor weighted sum or product of a maximum heart rate, upward slope, anddownward slope of a maximum effort cycle.

Once a capacity index is determined, an exercise regimen can begenerated. A heart wave index can also be used to generate the regimen.For example, a metric, such as the capacity index or heart wave index,can be received. Then, an individualized exercise regimen can begenerated using an algorithm that relates the metric to the regimen. Oneor both of the receiving and generating steps can use a look-up table.FIG. 7 shows illustrative look-up table 700. Look-up table 700 includesa plurality of capacity indices 720 a–720 m and a plurality ofpredetermined exercise regimens 710 a–710 m that are respectively linkedto the capacity indices. Capacity indices 720 a–720 m range from 115 to180 in steps of five units but can have any range and any size steps.

The use of a look-up table can involve rounding the received metric to anearest multiple of five or ten units, and then prescribing the exerciseregimen corresponding to the rounded number. For example, a receivedindex of 142 can be rounded to 140 (index 720 d). Then, using look-uptable 700, exercise regimen 710 d can be selected and prescribed.

Exercise regimens 710 a–710 m can be empirically generated. In thiscase, the regimens preferably account for the wave nature of cardiacactivity and apply the principles for therapeutic treatment andbio-rhythmic feed back taught by Dardik, U.S. Pat. Nos. 5,800,737,5,752,521, 5,163,439, and 5,007,430, incorporated by reference herein.Appendix A, for example, contains an actual set of exercise regimensdesigned for individual's with capacity indices ranging from 115 to 180units. The exercise regimens of Appendix A can be used, for example, inlook-up table 700.

Each of regimens 710 a–710 m can include a plurality of exercisesessions to be performed by the individual over a time period. The timeperiod can be any convenient period of time, such as about one lunarmonth. Each exercise session preferably includes a plurality of exercisecycles. The exercise cycles can include one or more warm-up cycles andone or more critical cycles that have target heart rates based on ametric.

The features of these exercise regimens can be better understood inconjunction with FIG. 8, which shows illustrative one month exerciseregimen 800 starting Apr. 25, 2000. Regimen 800 is designed forindividuals with capacity index 810 having a nominal value of about 115units. Regimen 800 includes eleven exercise sessions 821–831 and restweek 832. Each of sessions 821–831 includes a plurality of exercisecycles, each of which is designated by a target heart rate and cancontain a break if desired.

The time period over which the sessions are performed can begin with aninitial rest period (not shown), end with a final rest period (rest week832), and include intervening rest periods (April 26, April 28–29, May1, May 3, May 5–6, May 8, May 10, May 12–13, May 15, and May 17) betweenthe exercise sessions. Intervening rest periods are preferably at leastabout one day long, while final rest period 832 can be between about 4days and about 10 days. Regimen 800 is to be performed over about fourweeks (including final rest week 823).

The sessions in an exercise regimen can be synchronized with a lunarcycle. In FIG. 8, for example, regimen 800 is scheduled to start on Apr.25, 2000 about three weeks prior to a full moon. The exercise sessionscan also be synchronized with a circadian rhythm of the individual. Forexample, in FIG. 8 sessions 821–824, which are to be performed duringthe first week of the regimen, are scheduled between 6 a.m. and 9 a.m.This time period corresponds to a period of low circadian activity.Sessions 825–827, which are to be performed during the second week ofthe regimen, are scheduled to be performed between 9 a.m. and 12 p.m.This time period corresponds to a period of moderate circadian activity.Sessions 828–831, which are to be performed in the third week arescheduled to be performed between 3 p.m. and 6 p.m. This periodcorresponds to a period of high circadian activity.

The regimens used in the present invention can have a plurality ofcritical cycles that have sequentially increasing target heart rates. Asused herein, a critical cycle is a cycle that has an associated targetheart rate (i.e., is not a warm-up cycle without a defined target heartrate). For example, in session 821 the target heart rates increasesequentially for the first four cycles from 94 beats per minute to 114beats per minute, and again increase sequentially for the last threecycles from 108 beats per minute to 118 beats per minute. It will beappreciated that the first set of four cycles has a lower initial targetheart rate than the second set of three cycles. Also, the initial targetheart rate of the second set can be lower than the final target heartrate of the first set. Preferably, the target heart rates for criticalcycles within an exercise session increase substantially superlinearlyfrom one cycle to the next.

Critical cycles can have target heart rates that range up to about 20beats above the metric being used. For example, sessions 830 and 831have critical cycles with target heart rates of 130 beats per minute,which is 15 beats per minute higher than the nominal capacity index(i.e., 115).

Substantially all exercise sessions include a maximum cycle that has atarget heart rate that is greater than that for its previous cycle.Preferably, the target heart rates for the maximum cycles increasesubstantially linearly from one session to the next. For example, insessions 821–831, the highest target heart rate in each sessionsequentially increases in small increments from 118 beats per minute to130 beats per minute (with the exception of a small decrease for session823). Also, a regimen can include exercise cycles that alternate withrest periods.

One or more sessions in a regimen can include one or more spike cycles,during which the individual is expected to attempt to reach the targetheart rate as rapidly as possible. In FIG. 8, for example, spike cyclesare designated by the symbol “S” which is located next to the targetheart rates.

The regimen can be divided into an earlier part and a later part, withthe later part having more spike cycles than the early part. Forexample, in FIG. 8, sessions 821–825 are scheduled to be performed inthe first week or so and include no spike cycles, while sessions 827–831are scheduled to be performed in the second and third weeks and includeseveral spike cycles.

Regimens provided by this invention can be accompanied by an instructionguide that includes instructions on how to perform the regimen. Forexample, an instruction could be included that directs the individual toabruptly stop exercising and to rest during a subsequent rest period. Aninstruction could also be included to exercise as vigorously as possibleduring a spike cycle.

The aforementioned methods can be implemented on systems that include ananalyzer that preferably is programmable with routines that are capableof processing data contained in a time trace.

For example, the analyzer can include one or more routines for derivingone or more cycle parameters (such as a maximum heart rate, an upwardslope, a downward slope, a peak heart rate, a resting heart rate, and abase line slope) from a time trace. The analyzer can also includeroutines that use regression analysis for fitting a parabola through aportion of the time trace, and routines for diagnosing abnormalphysiological conditions by comparing measured parameters with those ina catalog that are linked with a physiological condition.

The analyzer can also include routines that compare a measured heartwave index to a target heart wave index and then modify an exerciseregimen in response to the comparison.

In an yet another embodiment the analyzer can include a routine toreceive a metric such as a heart wave index or a capacity index, aroutine to generate an exercise regimen using an algorithm that relatesthe metric to the regimen, and a routine to provide the individual withthe exercise regimen. The algorithm that relates the metric to theexercise regimen can use, for example, a previously prepared look-uptable.

As used herein, electronic networks could include a local area network,a wireless network, a wired network, a wide area network, the Internet,and any combination thereof. An electronic network can provide links touser interfaces used for sending or receiving data. The interfaces canbe any one or more of commercially available interface devices such as aweb page, a web browser, a plug-in, a display monitor, a computerterminal, a modem, an audio device, a tactile device (e.g., vibratingsurface, etc.), or any combination thereof.

In accordance with the present invention, software (i.e., instructions)for controlling the aforementioned systems can be provided oncomputer-readable media. It will be appreciated that each of the steps(described above in accordance with this invention), and any combinationof these steps, can be implemented by computer program instructions.These computer program instructions can be loaded onto a computer orother programmable apparatus to produce a machine, such that theinstructions which execute on the computer or other programmableapparatus create means for implementing the functions specified in theflowchart block or blocks. These computer program instructions can alsobe stored in a computer-readable memory that can direct a computer orother programmable apparatus to function in a particular manner, suchthat the instructions stored in the computer-readable memory produce anarticle of manufacture including instruction means which implement thefunction specified in the flowchart block or blocks. The computerprogram instructions can also be loaded onto a computer or otherprogrammable apparatus to cause a series of operational steps to beperformed on the computer or other programmable apparatus to produce acomputer implemented process such that the instructions which execute onthe computer or other programmable apparatus provide steps forimplementing the functions specified in the flowchart block or blocks.

It will be understood that the foregoing is only illustrative of theprinciples of the invention, and that various modifications can be madeby those skilled in the art without departing from the scope and spiritof the invention.

Appendix A

REGIMEN beginning Apr. 25 CAPACITY INDEX: 115'S 6–9 AM 6–9 AM 6–9 AM 6–9AM Tue Apr. 25 Thu Apr. 27 Sun Apr. 30 Tue May 2 94 98 100 102 103 109107 109 111 114 112 116 114 5 min. break 115 117 10 min. break 111 119122 108 117 115 120 118 9–12 AM 9–12 AM 9–12 AM Thu May 4 Sun May 7 TueMay 9 104 108 111 114 116 118 (S) 118 (S) 122 (S) 124 (S) 122 3–6 PM 3–6PM 3–6 PM 3–6 PM Thu May 11 Sun May 14 Tue May 16 Thu May 18 106 110 113115 115 118 (S) 118 (S) 121 (S) 119 121 (S) 121 (S) 130 (S) 123 (S) 124(S) 122 (S) 120 (S) 130 (S) 124 CAPACITY INDEX: 120'S 6–9 AM 6–9 AM 6–9AM 6–9 AM Tue Apr. 25 Thu Apr. 27 Sun Apr. 30 Tue May 2 96 100 102 104102 112 110 112 114 117 116 120 118 5 min. break 119 121 10 min. break114 123 126 111 121 119 124 122 9–12 AM 9–12 AM 9–12 AM Thu May 4 SunMay 7 Tue May 9 106 110 113 118 120 122 (S) 123 (S) 127 (S) 129 (S) 1273–6 PM 3–6 PM 3–6 PM 3–6 PM Thu May 11 Sun May 14 Tue May 16 Thu May 18108 112 115 117 119 122 (S) 121 (S) 125 (S) 123 126 (S) 125 (S) 135 (S)128 (S) 129 (S) 127 (S) 125 (S) 135 (S) 129 CAPACITY INDEX: 125'S 6–9 AM6–9 AM 6–9 AM 6–9 AM Tue Apr. 25 Thu Apr. 27 Sun Apr. 30 Tue May 2 98102 104 106 105 115 114 115 118 121 120 124 122 5 min. break 124 125 10min. break 118 128 131 114 125 123 129 127 9–12 AM 9–12 AM 9–12 AM ThuMay 4 Sun May 7 Tue May 9 118 112 115 121 123 126 (S) 127 (S) 132 (S)134 (S) 132 3–6 PM 3–6 PM 3–6 PM 3–6 PM Thu May 11 Sun May 14 Tue May 16Thu May 18 110 114 117 119 122 125 (S) 124 (S) 129 (S) 127 130 (S) (BD)129 (S) 140 (S) 133 (S) 134 (S) 131 (S) 129 (S) 140 (S) 134 CAPACITYINDEX: 130'S 6–9 AM 6–9 AM 6–9 AM 6–9 AM Tue Apr. 25 Thu Apr. 27 SunApr. 30 Tue May 2 100 104 106 108 107 118 117 118 121 124 124 128 126 5min. break 128 129 10 min. break 121 132 135 117 129 127 133 131 9–12 AM9–12 AM 9–12 AM Thu May 4 Sun May 7 Tue May 9 110 114 117 125 127 130(S) 132 (S) 137 (S) 139 (S) 137 3–6 PM 3–6 PM 3–6 PM 3–6 PM Thu May 11Sun May 14 Tue May 16 Thu May 18 112 116 119 121 126 129 (S) 127 (S) 133(S) 131 135 (S) 133 (S) 145 (S) 138 (S) 139 (S) 136 (S) 134 (S) 145 (S)139 CAPACITY INDEX: 135'S 6–9 AM 6–9 AM 6–9 AM 6–9 AM Tue Apr. 25 ThuApr. 27 Sun Apr. 30 Tue May 2 102 106 108 110 110 121 121 121 125 128128 132 130 5 min brk 133 133 10 min brk 125 137 140 120 133 131 138 1369–12 AM 9–12 AM 9–12 AM Thu May 4 Sun May 7 Tue May 9 112 116 119 128130 134 (S) 136 (S) 142 (S) 144 (S) 142 3–6 PM 3–6 PM 3–6 PM 3–6 PM ThuMay 11 Sun May 14 Tue May 16 Thu May 18 114 118 121 123 114 118 (S) 121(S) 123 (S) 135 139 (S) 137 (S) 150 (S) 143 (S) 144 (S) 140 (S) 138 (S)150 (S) 144 CAPACITY INDEX: 140'S 6–9 AM 6–9 AM 6–9 AM 6–9 AM Tue Apr.25 Thu Apr. 27 Sun Apr. 30 Tue May 2 104 108 110 112 112 124 123 124 128132 132 136 134 5 min. break 136 137 10 min. break 128 141 144 124 137135 142 140 9–12 AM 9–12 AM 9–12 AM Thu May 4 Sun May 7 Tue May 9 114118 121 132 134 138 (S) 141 (S) 147 (S) 149 (S) 147 3–6 PM 3–6 PM 3–6 PM3–6 PM Thu May 11 Sun May 14 Tue May 16 Thu May 18 116 120 123 125 133136 (S) 133 (S) 141 (S) 139 144 (S) 141 (S) 155 (S) 148 (S) 149 (S) 145(S) 141 (S) 155 (S) 149 CAPACITY INDEX: 145'S 6–9 AM 6–9 AM 6–9 AM 6–9AM Tue Apr. 25 Thu Apr. 27 Sun Apr. 30 Tue May 2 106 110 112 114 115 128127 128 132 137 137 141 139 5 min. break 141 142 10 min. break 132 146149 128 142 139 147 145 9–12 AM 9–12 AM 9–12 AM Thu May 4 Sun May 7 TueMay 9 116 120 123 135 138 142 (S) 145 (S) 152 (S) 154 (S) 152 3–6 PM 3–6PM 3–6 PM 3–6 PM Thu May 11 Sun May 14 Tue May 16 Thu May 18 118 122 125127 137 140 (S) 136 (S) 145 (S) 143 148 (S) 145 (S) 160 (S) 153 (S) 154(S) 149 (S) 145 (S) 160 (S) 154 CAPACITY INDEX: 150'S 6–9 AM 6–9 AM 6–9AM 6–9 AM Tue Apr 25 Thu Apr. 27 Sun Apr. 30 Tue May 2 108 112 114 116117 130 129 130 135 140 140 144 142 5 min. break 144 145 10 min. break135 150 153 131 145 143 151 149 9–12 AM 9–12 AM 9–12 AM Thu May 4 SunMay 7 Tue May 9 118 122 125 139 141 146 (S) 150 (S) 157 (S) 159 (S) 1573–6 PM 3–6 PM 3–6 PM 3–6 PM Thu May 11 Sun May 14 Tue May 16 Thu May 18120 124 127 129 140 143 (S) 139 (S) 149 (S) 147 153 (S) 149 (S) 165 (S)158 (S) 159 (S) 154 (S) 150 (S) 165 (S) 159 CAPACITY INDEX: 160'S 6–9 AM6–9 AM 6–9 AM 6–9 AM Tue Apr. 25 Thu Apr. 27 Sun Apr. 30 Tue May 2 112116 118 120 122 136 135 136 142 148 148 152 150 5 min. break 152 153 10min. break 142 159 162 138 153 151 160 158 9–12 AM 9–12 AM 9–12 AM ThuMay 4 Sun May 7 Tue May 9 122 126 129 146 148 154 (S) 159 (S) 167 (S)169 (S) 167 3–6 PM 3–6 PM 3–6 PM 3–6 PM Thu May 11 Sun May 14 Tue May 16Thu May 18 124 128 131 133 147 150 (S) 145 (S) 157 (S) 155 162 (S) 157(S) 175 (S) 168 (S) 169 (S) 163 (S) 159 (S) 175 (S) 169 CAPACITY INDEX:170'S 6–9 AM 6–9 AM 6–9 AM 6–9 AM Tue Apr. 25 Thu Apr. 27 Sun Apr. 30Tue May 2 116 120 122 124 125 142 141 142 149 156 156 160 158 5 minbreak 160 161 10 min. break 149 168 171 145 161 159 169 167 9–12 AM 9–12AM 9–12 AM Thu May 4 Sun May 7 Tue May 9 126 130 133 153 155 162 (S) 168(S) 177 (S) 179 (S) 177 3–6 PM 3–6 PM 3–6 PM 3–6 PM Thu May 11 Sun May14 Tue May 16 Thu May 18 128 132 135 137 154 157 (S) 151 (S) 165 (S) 163171 (S) 165 (S) 185 (S) 178 (S) 179 (S) 172 (S) 168 (S) 185 (S) 179CAPACITY INDEX: 175'S 6–9 AM 6–9 AM 6–9 AM 6–9 AM Tue Apr. 25 Thu Apr.27 Sun Apr. 30 Tue May 2 118 122 124 126 130 145 145 145 153 160 160 164162 5 min. break 165 165 10 min. break 153 173 176 148 165 163 174 1729–12 AM 9–12 AM 9–12 AM Thu May 4 Sun May 7 Tue May 9 128 132 135 156158 166 (S) 172 (S) 182 (S) 184 (S) 182 3–6 PM 3–6 PM 3–6 PM 3–6 PM ThuMay 11 Sun May 14 Tue May 16 Thu May 18 130 134 137 139 157 160 (S) 154(S) 169 (S) 167 175 (S) 169 (S) 190 (S) 183 (S) 184 (S) 176 (S) 172 (S)190 (S) 184 CAPACITY INDEX: 180'S 6–9 AM 6–9 AM 6–9 AM 6–9 AM Tue Apr.25 Thu Apr. 27 Sun Apr. 30 Tue May 2 120 124 126 128 132 148 147 148 156164 164 168 166 5 min break 168 169 10 min break 156 177 180 152 169 167178 176 9–12 AM 9–12 AM 9–12 AM Thu May 4 Sun May 7 Tue May 9 130 134137 160 162 170 (S) 177 (S) 187 (S) 189 (S) 187 3–6 PM 3–6 PM 3–6 PM 3–6PM Thu May 11 Sun May 14 Tue May 16 Thu May 18 132 136 139 141 161 164(S) 157 (S) 173 (S) 171 180 (S) 173 (S) 195 (S) 188 (S) 189 (S) 181 (S)177 (S) 195 (S) 189

1. A computer-readable medium containing instructions for prescribing anexercise regimen for an individual, said instructions comprising:instructions to receive a metric indicative of said individual'sphysiological condition; instructions to generate said exercise regimenusing an algorithm that relates said metric to said regimen;instructions to export said exercise regimen to said individual using anoutput device; and instructions for generating a guide based on saidregimen, said guide directing said individual in real-time on how toexercise, wherein said metric is based on heart rate information of anindividual obtained during an exercise test.
 2. The computer-readablemedium of claim 1 wherein said exercise regimen comprises a plurality ofexercise sessions to be performed by said individual, wherein each ofsaid plurality of exercise sessions comprising: at least one warm upcycle; and at least one critical cycle that has a target heart rate,wherein said target heart rate is based on said metric.
 3. Thecomputer-readable medium of claim 1 further comprising instructions todetermine a capacity index based on an electronic file containing a timetrace of a heart rate of said individual obtained during said exercisetest that includes a plurality of test cycles and at least one maximumeffort cycle, wherein said instructions to determine a capacity indexcomprises: instructions to determine at least one maximum effort cycleparameter; and instructions to determine said capacity index based onsaid at least one maximum effort cycle parameter.
 4. Thecomputer-readable medium of claim 3, wherein said maximum effort cycleparameter is selected from a group consisting of a first peak heart ratecorresponding to a maximum heart rate monitored during said maximumeffort cycle.
 5. The computer-readable medium of claim 3, wherein saidinstructions to determine a capacity index further comprisesinstructions to determine another parameter for use in said capacityindex, said another parameter being selected from a group consisting ofa second peak heart rate monitored during another of said plurality oftest cycles that is not said maximum effort cycle, an upward slope ofsaid heart rate monitored during a part of a stress portion of at leastone of said plurality of test cycles, and a downward slope of said heartrate monitored during a part of a relaxation portion of the at least oneof said plurality of test cycles.
 6. A computer-readable mediumcontaining instructions for prescribing an exercise regimen for anindividual, said instructions comprising: instructions to receive ametric indicative of said individual's physiological condition;instructions to generate said exercise regimen using an algorithm thatrelates said metric to said regimen; instructions to export saidexercise regimen to said individual using an output device; instructionsfor generating a guide based on said regimen, said guide directing saidindividual in real-time on how to exercise; and instructions forcommunication over links within a system wherein said links comprise anelectronic network selected from a group consisting of local areanetworks, wireless networks, wired networks, wide area networks, theInternet and any combination thereof.
 7. A computer-readable mediumcontaining instructions for prescribing an exercise regimen for anindividual, said instructions comprising: instructions to receive ametric indicative of said individual's physiological condition;instructions to generate said exercise regimen using an algorithm thatrelates said metric to said regimen; instructions to export saidexercise regimen to said individual using an output device; instructionsfor generating a guide based on said regimen, said guide directing saidindividual in real-time on how to exercise; and instructions foraccessing linked databases including said guide, through an electronicnetwork, wherein said network is selected from a group comprising of alocal area network, a wide area network, a wired network, a wirelessnetwork, the Internet and any combination thereof.
 8. Acomputer-readable medium containing instructions for prescribing anexercise regimen for an individual, said instructions comprising:instructions to receive a metric indicative of said individual'sphysiological condition; instructions to generate said exercise regimenusing an algorithm that relates said metric to said regimen;instructions to export said exercise regimen to said individual using anoutput device; instructions for generating a guide based on saidregimen, said guide directing said individual in real-time on how toexercise; and instructions for controlling a system through anelectronic network, wherein said network is selected from a groupcomprising of a local area network, a wide area network, a wirednetwork, a wireless network, the Internet and any combination thereof.9. A computer-readable medium containing instructions for prescribing anexercise regimen for an individual, said instructions comprising:instructions to receive a metric indicative of said individual'sphysiological condition; instructions to generate said exercise regimenusing an algorithm that relates said metric to said regimen;instructions to export said exercise regimen to said individual using anoutput device; instructions for generating a guide based on saidregimen, said guide directing said individual in real-time on how toexercise; and instructions for communication external to a systemthrough user interfaces selected from a group comprising of web pages,display monitors, terminals, modems, audio devices, wired devices, andwireless devices or any combination thereof.